Apparatus for recovering lead shot from the earth



y 1, 1956 R. A. WACHSMITH 2,756,978

APPARATUS FOR RECOVERING LEAD SHOT FROM THE EARTH Filed May 5, 1952 2 Sheets-Sheet 1 INVEYE ATTORNEYS RICHARD A. WACHSMITH y 31, 1956 R. A. WACHSMITH 2,756,978

APPARATUS FOR RECOVERING LEAD SHOT FROM THE EARTH Filed May 5, 1952 2 Sheets-Sheet 2 RICHARD A. WACHSMITH INVENTOR I ATTORNEYS 1 2,756,978 APPARATUS FOR RECOVERING LEAD SHOT FROM THE EARTH Richard A. Wachsmith, Yakima, Wash. Application May 5, 1952, Serial N0. 286,067 2 Claims. (Cl. 262-2) My invention relates to the recovery of lead shot from shooting ranges, and, more particularly, to apparatus for recovering lead shot from the earth.

Briefly, the mining machine comprises a vehicle having flail-like flexible metal diggers disposed to throw earth material into a housing, blower means for separating the dirt content from the other materials thrown into said housing, and screen means for separating materials of the size of lead shot from larger heavy material not separated by the blower. The separated dirt content is deposited in the path of the machine behind the digger and the large heavy material such as rocks is directed to the side of the machine into the area alongside that being mined.

On trap-shooting ranges and the like, after a period of use, a considerable amount of lead shot is deposited in the upper layer of earth and it becomes desirable to recover this shot as there is enough concentrated in such area to make the same commercially feasible. It will be understod, however, that unless the recovery opera tion is very eflicient, the cost will be prohibitive. One means for economizing is to have a mobile unit so that the separating mechanism will pass over the area instead of having to transport the earth material to a stationary machine. The top layer of earth in such area is composed mostly of dirt with some rock content. To separate the materials efiiciently, it is important to have an easy method of separating the dirt content and it has been found that this can be done with blower means. The heavier content, separated from the dirt content by means of the blower, can be separated into materials of a size larger than the lead shot, and materials of the size of the lead shot, by means of a screen. By these means the economical recovery of the lead shot is possible.

The objects of my invention include, therefore, to provide a mobile mining machine for recovery of lead shot from a shooting range, to devise means for digging or flailing the earth material efiiciently and to devise means for efficiently separating the lead shot from other mined material, to provide an improved method of recovering lead shot from an area having a considerable deposit of the same, and to construct a mobile mining machine of economical structure and easy maintenance.

My invention will be best understood, together with other objects and advantages thereof, by a reading of the following description with reference to the drawings in which:

Figure 1 is a side view of a specific embodiment of my mobile mining machine;

Figure 2 is a view similar to Figure 1 only showing most of the parts in section;

Figure 3 is a perspective view of the flail-like digger unit;

Figure 4 is a sectional view taken on line 44 of Figure 2;

Figure 5 is a side view, on an enlarged scale and in fragmentary form, of the means for adjusting the position of the digger unit;

Figure 6 is an enlarged perspective view of the front wheel assembly; and

Figure 7 is an enlarged fragmentary view, partly in section, of the securing means for the screens.

The mining machine construction It has been found most economical to provide the mining machine in a mobile assembly. The machine States Patent 0 2,756,978 Patented July 31, 1956 shown in Figure 1 has a housing 10 supported at the rear by a pair of wheels 12, secured to housing 10 by the framework 14, and supported at the front by a single wheel member 16, secured to the forward end of the housing by yoke member 18 permitting wheel 16 to pivot about a vertical axis. Secured to yoke 18 is a draw bar assembly 20, whereby the mining machine may be drawn by a tractor or the like in the manner of a trailer. Wheel 16 is formedof two opposed frusto-conical portions, 24, 26. This structure has a function of smoothing and slightly crowning the ground in front of the digger assembly particularly when the earth is loose.

Mounted on housing 10 is a gasoline engine 30 providing power for the digger unit and blower. Motor 30 has a multiple sheave 32 on which is positioned a plurality of V-belts 34 and 36 running to sheaves 33 and 35 of the digger unit and blower, respectively. Sheave 32 should rotate at a considerable speed as both the digger and the blower operate at high speeds.

The flail-like digger assembly is best shown in Figure 3 and comprises a cylindrical-shaped rotary member 40 which is hollow and preferably formed of metal, and has a multiplicity of cables 42 running diametrically therethrough. Rotary member 40 has a series of openings arranged in rows to accommodate cables 42, and each opening is bordered by a securing ring 44 to which the cables may be anchored as by setscrews or by welding. The extending ends of the cables are of course somewhat flexible which prevents their being injured on striking a large rock or the like as would be the case with a rigid digger. In striking the same obstacle, the cables bend or divide and suffer relatively small injury. The cables are preferably five-eighths of an inch in diameter and extend beyond member 40 for seven inches at each end. The digger assembly is rotated in the direction indicated by the arrow in Figure 2, and, in striking the ground, throws the earth material its strikes forwardly into the machine. It will be seen that the rotary unit has to revolve at considerable speed in order to throw the material as indicated in Figure 2 and from six hundred to one thousand revolutions per minute has proved to be quite satisfactory, depending on conditions of ground surface.

To assist in directing the thrown material into housing 10, a bafile structure is positioned just forward of the digger unit as perhaps best shown in Figure 2. This includes the inclined and depending housing wall 5t) and the metal sheet 52 adjustably pivoted at 53 to the housing at its upper edge and having its lower end disposed to drag on the ground immediately forward of the diggers 42. It will be seen from Figure 2 that by this construction, the earth material follows the path indicated in Figure 2 through the bottom of ingress opening 54 of the housing 10.

Blower 60 is positioned forward in the housing and is preferably of a centrifugal type having a series of blades 62. This is a heavy duty unit designed to direct a heavy current of air rearwardly in housing it) of such intensity as to block and blast dirt and sand materials of the earth thrown by the digger unit. Such materials are directed to the rear of housing 16 and over the digger unit out of the back of the machine through egress opening 64 onto the path of travel of housing behind the digger assembly. By depositing the dirt material at this point, it will be seen that the same will not be reworked as it would be if the same were directed into unworked areas. A fan revolving at approximately twelve hundred revolutions per minute is eflicient for this action.

The action of diggers 42 and blower 60 are most eflicient when the ground is dry as the earth then does not resist digging and dirt material is blown apart more easily from the other thrown material. This is generally not a problem as the shooting ranges are often located in arid areas where at least in the middle of the summer the ground is very dry.

A pair of screens 70 and '72 are positioned in the forward end of the housing in the path of travel of heavy thrown materials such as rocks, not separated by the air from fan 69. The screens are shown as being posi tioned between ingress opening 54 and fan 60 as it has been found that the machine operates most efliciently in this manner even though it will be apparent that they could be otherwise disposed. The objects falling on screens '70 and 72 are generally rocks and lead shot. The rock material of a larger size than the lead shot is separated by the first screen 79 which has mesh of a size suitable for this separation. Screen 70 discharges the larger rock downwardly into chute 74 which guides the rock to the side of the machine. As will be described later, these rocks are directed to the side of the machine onto a marginal or already-worked area so that the rocks will not again be separated in working the remainder of the area. Approximately five thirty-seconds of an inch mesh screen is suitable for screen 70, although this may be varied for unusual sizes of shot.

The shot and other small heavy materials falling through screens 79 are guided by screen 72 into the collecting bin 76. The function of screen '72 is to permit passage of air, while serving as a baffle for the lead shot, so it may be of fine mesh. It has been found that the lead shot collected in this bin has been separated efficiently from most materials so that the separation from small rocks also falling into the bin is an easy matter. At the same time a large percentage of the lead shot in the strip, substantially all, is worked by the machine and is deposited in bin 76.

Adjusting means for the rotary digger is provided by supporting frames 80, on each side, each pivotally secured at its upper end to rod 82 operating in slot 84. Bolt 88, positioned at one end of slot 84 in a threaded opening, operates slide 86 which bears against rod 82. The lower end of beam 80 is supported by a rod 90 pivotally secured to frame 30. Screw jack 92 is pivotally secured to housing at 94 and the upper end of rod 90 is adjustable in screw jack 92, by the operation of handle 96. By these means diggers 42 may be easily adjusted to control the depth of digging, and the diggers are usually adjusted to the depth of approximately one and one-half inches.

Screens '79 and '72 may be variably positioned through adjustable securing means acting in the slots of arms 100, 102 respectively. One form of securing means is shown in Figure 7 and includes bolt 104 acting in slot 106 and secured by nut 108.

The n'zethod of mining The method of mining the area having a deposit of lead shot is to work the area with the mobile machine in strips with consecutively Worked strips lying side by side. This may be easily accomplished by following an annular or rectangular path of increasing or decreasing dimensions. As before mentioned it is best to work the area when it is in a dry condition so that the dirt and sand can be separated from stones and the like by air means with facility. The dirt is thrown forwardly and upwardly and is there struck by a current of air of such intensity as to move materials of less weight than lead shot rearwardly and to direct this blown material, mostly dirt, into the strip in the previously worked portion. By either directing the dirt immediately behind the machine or to the side of the machine facing previously worked strips, the reworking of the same dirt in finishing the mining of the area is avoided. The heavy materials not separated by the current of air are blocked by screen means which separate materials of a larger size than lead shot and direct the larger materials to the side of the strip which has already been Worked, again to avoid reworking these materials. The lead shot and accompanying materials passing through these screen means are then collected.

This method of recovering lead shot has proved to be efficient in the percentage of recovery and of economical cost so that the mining is commercially desirable. The equipment is of inexpensive construction and low maintenance.

It will be noted that the wheel and drawbar assembly may be removed and the weight of the machine supported by the tractor drawbar in extremely sandy terrain.

Having thus described my invention, I claim:

1. A mobile machine for the collection of heavy metallic particles such as lead shot and the like, comprising: a hollow housing elongated from front to rear having an air outlet in its rear and fan means supported within the forward portion of said housing, said housing having an air inlet adjacent the fan operative'to pass air from outside the housing to said fan means, said fan means being arranged to direct an air stream rearwardly therefrom toward said air outlet, ground engaging means supporting said housing for movement thereof in an end forward direction, said housing having an inlet in its underside intermediate its ends in spaced relation forward of said air outlet, a sloping deflector secured to said housing adjacent the forward portion of the underside inlet and extending rearwardly and downwardly therefrom toward the ground, a rotary sweeping device composed of a multiplicity of flexible flails and transversely disposed beneath said housing rearward of said underside inlet and deflector and forward of said air outlet, means on said machine to rotate said sweeping device so that the flexibl flails on the underside of said device move forwardly toward said deflector to throw ground surface materials into said housing, and means in said housing between said underside inlet and fan means for separating large and small earth and metallic particles.

2. A mobile machine for the collection of heavy metallic particles such as lead shot and the like, comprising: a hollow housing elongated from front to rear having an air outlet in its rear and fan means supported within the forward portion of said housing, said housing having an air inlet adjacent the fan operative to pass air from outside the housing to said fan means, said fan means being arranged to direct an air stream rearwardly therefrom toward said air outlet, ground engaging means supporting said housing for movement thereof in an end forward direction, said housing having an underside inlet intermediate its ends in spaced relation forward of said air outlet, a sloping deflector plate having its upper end pivotally secured to said housing adjacent the forward portion of the underside inlet and having its lower, trailing end extending rearwardly and downwardly and free to drag on the ground, a rotary sweeping device composed of a multiplicity of flexible flails and transversely disposed beneath said housing rearward of said underside inlet and deflector plate and forward of said air outlet, means on said machine to rotate said sweeping device so that th flexible flails on the underside of said device move forwardly toward said deflector to throw ground surface materials into said housing, and screen means in said housing between said underside inlet and fan means for separating large and small earth and metallic particles.

References Cited in the file of this patent UNITED STATES PATENTS Re. 1,366 Westinghouse Dec. 16, 1862 234,255 Dennen et al. Nov. 9, 1880 1,330,963 Turk Feb. 17, 1920 1,702,146 Yockers Feb. 12, 1929 2,148,568 McBrady Feb. 28, 1939 2,196,880 Van Voorhis et al. Apr. 9, 1940 FOREIGN PATENTS 661,949 France Mar. 12, 1929 370,694 Germany July 23, 1921 

1. A MOBILE MACHINE FOR THE COLLECTION OF HEAVY METALLIC PARTICLES SUCH AS LEAD SHOT AND THE LIKE, COMPRISING: A HOLLOW HOUSING ELONGATED FORM FRONT TO REAR HAVING AN AIR OUTLET IN ITS REAR AND FAN MEANS SUPPORTED WITHIN THE FORWARD PORTION OF SAID HOUSING, SAID HOUSING HAVING AN AIR INLET ADJACENT THE FAN OPERATIVE TO PASS AIR FROM OUTSIDE THE HOUSING TO SAID FAN MEANS, SAID FAN MEANS BEING ARRANGED TO DIRECT AN AIR STREAM REARWARDLY THEREFROM TOWARD SAID AIR OUTLET, GROUND ENGAGING MEANS SUSPROTING SAID HOUSING FOR MOVEMENT THEREOF IN AN END FORWARD DIRECTION, SAID HOUSING HAVING AN INLET IN ITS UNDERSIDE INTERMEDIATE ITS ENDS IN SPACED RELATION FORWARD OF SAID AIR OUTLET, A SLOPING DEFLECTOR SECURED TO SAID HOUSING ADJACENT THE FORWARD PORTION OF THE UNDERSIDE INLET AND EXTENDING REARWARDLY AND DOWNWARDLY THEREFROM TOWARD THE GROUND, A ROTARY SWEEPING DEVICE COMPOSED OF A MULITPLICITY OF FLEXIBLE FLAILS AND TRANSVERSELY DISPOSED BENEATH SAID HOUSING REARWARD OF SAID UNDERSIDE, INLET AND DEFLECTOR AND FORWARD OF SAID AIR OUTLET, MEANS ON SAID MACHINE TO ROTATE SAID SWEEPING DEVICE SO THAT THE FLEXIBLE FLAILS ON THE UNDERSIDE OF SAID DEVICE MOVE FORWARDLY TOWARD SAID DEFLECTOR TO THROW GROUND SURFACE MATERIALS INTO SAID HOUSING, AND MEANS IN SAID HOUSING BETWEEN SAID UNDERSIDE INLET AND FAN MEANS FOR SEPARATING LARGE AND SMALL EARTH AND METALLIC PARTICLES. 